Question:
In an isosceles triangle ABC, if AB = AC = 25 cm and BC = 14 cm, the measure of altitude from A on BC is
(a) 20 cm
(b) 22 cm
(c) 18 cm
(d) 24 cm
Solution:
Given: In an isosceles triangle ABC, AB = AC = 25 cm and BC = 14cm.
To find: Measure of altitude from A on BC
Since AD ⊥ BC, so BD = CD = BC2=14 cm2=7 cm
In right ∆ABD,
AB2=AD2+BD2⇒AD2=AB2-BD2⇒AD2=252-72=625-49=576⇒AD=24 cm
We got the result as $(d)$